In the Canadian Forces, lieutenant-colonel (LCol, French: lieutenant-colonel or lcol) is a rank for officers who are in the Canadian Army or the Royal Canadian Air Force, equal to commander for officers who are in the Royal Canadian Navy. A lieutenant-colonel is the second-highest rank of senior officer. A lieutenant-colonel is senior to a major or lieutenant-commander, and junior to a colonel or naval captain.

The rank insignia for a lieutenant-colonel on air force uniforms is three 1 cm stripes of braid, worn on the cuffs of the service-dress jacket, and on slip-ons on other uniforms. On army uniforms, the rank insignia is one pip and a crown.

Lieutenant-colonels are addressed by rank and name and thereafter by subordinates as "Sir" or "Ma'am".